GemFan produces some of the finest propellers for Multi-Rotor use, and they are available in a variety of colors and materials. All of the different sizes are available in both normal and reverse rotation as needed for use in multi-rotor craft.

The 6x3 props have a 5mm hole drilled in the front side of the hub. Included with the prop is a set of OD adapter rings that step down the center hole of the prop to allow it fit on 2mm, 3mm, or 4mm motor shafts. If you have a larger threaded shaft on your prop adapter, the center hole can be reamed out to a larger size as needed.

Included with each prop is a set of adapter rings that step down the center hole diameter of the prop. If you have a larger threaded shaft on your prop adapter, the center hole can be reamed out to a larger size as needed. - See more at: http://www.altitudehobbies.com/multicopter-props-1/mini-props-5-7/gemfan-6030-2-blade-nylon-prop-set-1x-cw-and-1x-ccw-green#sthash.g6vo1hxz.dpuf

Included with each prop is a set of adapter rings that step down the center hole diameter of the prop. If you have a larger threaded shaft on your prop adapter, the center hole can be reamed out to a larger size as needed. - See more at: http://www.altitudehobbies.com/multicopter-props-1/mini-props-5-7/gemfan-6030-2-blade-nylon-prop-set-1x-cw-and-1x-ccw-green#sthash.g6vo1hxz.dpuf